21258514368 has 896 divisors, whose sum is σ = 81930240000. Its totient is φ = 5364817920.

The previous prime is 21258514367. The next prime is 21258514373. The reversal of 21258514368 is 86341585212.

21258514368 is a `hidden beast` number, since 2 + 1 + 2 + 585 + 1 + 4 + 3 + 68 = 666.

It is a super-3 number, since 3×21258514368³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21258514367) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 238859668 + ... + 238859756.

It is an arithmetic number, because the mean of its divisors is an integer number (91440000).

Almost surely, 2^21258514368 is an apocalyptic number.

21258514368 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21258514368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40965120000).

21258514368 is an abundant number, since it is smaller than the sum of its proper divisors (60671725632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21258514368 is a wasteful number, since it uses less digits than its factorization.

21258514368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175 (or 145 counting only the distinct ones).

The product of its digits is 460800, while the sum is 45.

The spelling of 21258514368 in words is "twenty-one billion, two hundred fifty-eight million, five hundred fourteen thousand, three hundred sixty-eight".